Today's electronic equipment may use a lot of electrical power. Many CPUs, GPUs or a LED PCBs actually behave like heat sources producing a lot of heat which needs to be eliminated to avoid damage and failure. One way of eliminating the produced heat is by forced convection cooling of the heat sources. A heat sink may be thermally coupled to the heat source, wherein the heat sink is cooled by blowing air along or through the heat sink. A particular category of heat sinks is the radial heat sink equipped with an axial fan. A radial heat sink comprises a central heat distributor connected to a plurality of radially extending fins. The axial fan is positioned so as to blow air between the fins. The fins will be cooled by the air, and therefore the heat distributor can distribute the heat coming from the heat source towards the fins. To obtain a satisfying result, the fins need to have a minimal length.
The required fin thickness increases strongly with the fin length (length from base to fin tip), according to a square relation as follows from the fin efficiency theory, which is well known under specialists in the thermal field. So it is desirable to keep the fin length as short as possible, for performance, weight and cost reasons.
Air flow from a fan may have a considerable speed (typically 2-10 m/s in consumer products) and deflection of the flow into another direction is associated with a pressure drop and loss of flow.
Publication US 2005/061478 A1 discloses a heat sink having a plurality of plates which are curved in a cross section perpendicular to a main axis. An example has been shown in which the plates are also curved in the axial direction.